Continuity within somatosensory cortical map shapes the integration of optogenetic input

Abstract

The topographic organization of sensory cortices is a prominent feature, but its functional role remains unclear. Particularly, how activity is integrated within a cortical area depending on its topography is unknown. Here, we trained mice expressing channelrhodopsin in cortical excitatory neurons to track a bar photostimulation that rotated smoothly over the primary somatosensory cortex (S1). When photostimulation was aimed at vS1, the area which contains a contiguous representation of the whisker array at the periphery, mice could learn to discriminate angular positions of the bar to obtain a reward. In contrast, they could not learn the task when the photostimulation was aimed at the representation of the trunk and legs in S1, where neighboring zones represent distant peripheral body parts, introducing discontinuities. Mice demonstrated anticipation of reward availability, specifically when cortical topography enabled to predict future sensory activation. These results are particularly helpful for designing efficient cortical sensory neuroprostheses.

Effects of indoor lighting environments on paper reading efficiency and brain fatigue: an experimental study

“…In our everyday thinking and cognitive activities, the frontal and parietal lobes are typically the most active brain regions (Sammer et al, 2007). Electroencephalography (EEG) is an important tool used to assess brain function by visualizing fluctuating brain activity on a two-dimensional plane (Foged et al, 2022;Lassagne et al, 2022). It records the spontaneous electrical activity of pyramidal dendrites in the brain cortex, effectively reflecting the degree of brain fatigue and cortical excitability (Lin et al, 2015).…”